Electrical incandescent lamp for series connection



March 28, 1939. I F WATERS 2,152,228

ELECTRICAL INCANDESCENT LAMP FOR SERIES CQNNECTIDNY Filed May @1937 rammed Mar. 28, 1939 g I l 2,152,228

UNITED STATES PATENT OFFICEQ' ELECTRICAL INOANDESCENT LAMP FOR scams commoner:

Harry F. Waters, New York, N. Y. Application May 5, 1937, Serial No.-140,840

1 Claim. (01. 176 24) The present invention relates to electrical insistance may be connected and provided in the candescent lamps, and, more particularly, to cord, it may be arranged in the lamp within electrical incandescent lamps particularlyadaptthe glass vessel thereof, in the base or in the ed for series connection. socket of the lamp, and it may be provided in a 5 It is an object of the present invention to. separate member or adaptor interposed between 6 provide an electrical incandescent lamp par the lamp base and the socket. When a setof ticularly for the purpose of series connection such lamps is connected in series and is con-. which is free from the disadvantages and in,- nected 'to a source'oi currentofsuitable voltconveniences of conventional series-connected age, current will flow through the filaments of lo lamps. g the lamps connected in series and through the 10 It is another object of the present invention resistance elements which are also connected in to provide a series-connected incandescent lamp series. However, if any one of the lamps will which can be' connected in series with a pluburn out and willinterrupt the main circuit of amy i lamps of the same type and which will the lamps, this will not cause all of the other not interruptthe circuit of the other lamps lamps to extinguish as this was the case with 16 when its filament burns out.v I the conventional lamps connected in series, be-

I It is a further object of the invention to procause the other lamps w b upplied with ourvide a series-connected incandescent lamp which rent through t y-p s' r i nce connected embodies a resistance element connected across across thelamp which has burnt out. Although 20 its filament, said resistance element being capathe other lamps will light more dimly due to the 20 bio of carrying sufllcient current for bringing in r a ed resistance in the circuit, they w the other lamps in the circuit to at least dim ll li ht with the single exception of the one incandescenoe. which has burnt out. This permits one to 10- It is also within contemplation of the prescate the burnt out lamp with at facility 50 ent invention to provide a novel and improved h t e a d lamp ay be replaced w a new 25 incandescent lamp for series connection which one at once. is simple. in construction and which may be The value of the resistance element is determanuiactured and sold at a low price. mined at best by experiment. The resistance.

Other and further objects and advantages of should be low enou h to permit sufficient curthe invention will become apparent from the rent to pass t light p the other lamps at least 30 following description taken in conjunction with very dimly. On the other hand, it is advanthe accompanying drawing, in which tageous to provide such high resistance as is.

Fig. 1 illustrates a vertical sectional view of comp w this function n View of the a lamp embodying the principles of the present fact that the current pa t u h the auxinvention; iliary circuit formed by the resistance elements 35 Fig. 2 depicts a diagrammatic view of the d not Perform any useful Work and is ly circuit and illustrates the way in which a pluconverted into heat.

rality of the novel lamps is connected; The invention will now be more fully described Fig. 3 is a view similar to Fig. 1 and shows a to those skilled in the art, reference being had 40 modified embodiment of the present invention; to the accompanying drawing. 40

and Referring now more particularly to Fig. 1, a

Fig. 4 illustrates a verti al sectional vi w of preferred embodiment of the invention is illus- I an adaptor to be used for th co versio f trated. A sealed glass vessel II is provided with conventional lamps into lamps embodying the filam t l2 of tungsten Carbon pp r invention. in conventional manner by lead-in wires l3 and 5 Broadly stated, according to the principles of H. Wires l3 and H a:e lead out of the glass my invention, I provide a plurality of incanvessel and are connectedtoaconventional threaddescent lamps having suitable sockets and wire ed orv screw base l6, and bottom contact l5 connections. I connect such plurality of these which are insulated from each other by a dilamps in series that the operating voltage of electric l1. Across wires l3 and I4 and within 50 the lamps multiplied by .the number of lamps the glass vessel is connected a resistance eleconnected in series approximately equals the ment l8. This resistance element may be in full line voltage. Across each lamp I connect a the form of a wire or coil of suitable resistance. resistance of suitable value which electrically It is also possible to provide the resistance eleby-passes the filament of the lamp. This rement in the form of a second or auxiliary fllau ment connected across the main filament or filament proper. This has the advantage that the current passed through the auxiliary filament is not wasted but is converted into radiant energy. In Fig. 2, a plurality of such lamps is shown connected in series. Each of lamps 2| is provided with a filament 22 and with a resistance element 28 within the glass vessel thereof.

From the preceding description, the operation of the improved series lamp will be readily understood by those skilled in the art. When the group of lamps connected in series is connected to a source of current of suitable voltage, current will pass through all of the filaments and through all of the resistance elements. As soon, however, as one of the filaments burns out, current will fiow only through the corresponding resistance element which will permit the other lamps to light at least dimly and to readily reveal the faulty lamp.-

The modified embodiment of the invention shown in Fig. 3 has a structure similar to that of Fig. 1 and comprises a sealed glass vessel ii, a filament 32, supporting wires 33 and 34 which areconnected to bottom contact 38 and base 34,

respectively, insulated by dielectric 31. Resistance element 38 is located in the base of the lamp and is connected between screw base 36 and bot tom contact 35. In view of the similarity of construction, the operation of this modified embodiment will be readily understood by those skilled in the art without any further explanation.

Fig. 4 depicts an adaptor adapted to be interposed between a conventional lamp and a conventional socket. The adaptor comprises an insulative body portion 4|, athreaded female portion 42 adapted to hold a lamp base, and a threaded male portion 43 integrally formed therewith and adapted to be inserted into a con- "ventional socket. Bottom contacts 44 and 45 are inserted and held by insulative rings 41 and 49 in the female and the male portions, respectively, and are connected electrically by a conductor 48. In the male portion of the'adaptor is located a resistance element 48 which is connected between members 43 and 45. When a conventional lamp is inserted into the threaded female portion 42, resistance element 48 will be connected across the lamp and will function in the same way as in the embodiments shown in Figs. 1 to 3.

Although the present invention has been described in connection with a few selected embodiments thereof, variations and modifications may beresorted to by those skilled in the art without departing from the spirit and scope of the present invention. I consider all of these variations and modifications as within the true spirit and scope of the present invention as disclosed by the present description and defined by the appended claim.

I claim:

An incandescent lamp for series connection comprising a sealed glass vessel, a filament in said vessel, lead-in wires extending into said vessel and forming a gas-tight seal therewith for supporting said filament, a base cemented to said vessel and having contacts therein electrically connected to said wires for passing current through said filament, and a resistance element located within said base and permanently connected across said wires and across said filament said resistance element being-so proportioned as to pass substantial current during the normal operation of said filament, and in case of rupture of said filament being capable of passing sufiicient current to the filaments of other lamps of the same type connected in series therewith to bring such filaments to at least dim incandescence.

HARRY F. WATERS. 

